Although sundials and nocturnals have been used for telling time for centuries and even combination instruments have been built, such as disclosed in Thomson U.S. Pat. No. 2,582,179 issued Jan. 8, 1952, and Fleming U.S. Pat. No. 3,073,032 issued Jan. 15, 1963, these combination devices require separately concentrically relatively movable circular scales, as well as outside equipment for their setting or proper operation, such as a clock or a light source for their initial setting. Furthermore, they are relatively complicated and require several parts which must be accurately made and adjustable with precision.